/**
 * 背景加水印
 * 姓名、部门”并列一行，“工号”换行。居中形式。
 */
function watermark(settings) {
	//默认设置
	var defaultSettings = {
		watermark_txt: settings,
		watermark_x: 0, //水印起始位置x轴坐标
		watermark_y: 15, //水印起始位置Y轴坐标
		watermark_rows: 10, //水印行数
		watermark_cols: 6, //水印列数
		watermark_x_space: -10, //水印x轴间隔
		watermark_y_space: 50, //水印y轴间隔
		watermark_color: "#aaa", //水印字体颜色
		watermark_alpha: 0.25, //水印透明度
		watermark_fontsize: "13px", //水印字体大小
		watermark_font: "微软雅黑", //水印字体
		watermark_width: 90, //水印宽度
		watermark_height: 50, //水印长度
		watermark_angle: 15, //水印倾斜度数
	};
	//采用配置项替换默认值，作用类似jquery.extend
	if (arguments.length === 1 && typeof arguments[0] === "object") {
		var src = arguments[0] || {};
		for (key in src) {
			if (src[key] && defaultSettings[key] && src[key] === defaultSettings[key])
				continue;
			else if (src[key]) defaultSettings[key] = src[key];
		}
	}

	var oTemp = document.createDocumentFragment();
	//获取页面最大宽度
	var page_width = document.documentElement.clientWidth;

	//获取页面最大高度
	var page_height = document.documentElement.clientHeight + 100;
	// var page_height = document.body.scrollHeight+document.body.scrollTop;
	//如果将水印列数设置为0，或水印列数设置过大，超过页面最大宽度，则重新计算水印列数和水印x轴间隔
	if (
		defaultSettings.watermark_cols == 0 ||
		parseInt(
			defaultSettings.watermark_x +
			defaultSettings.watermark_width * defaultSettings.watermark_cols +
			defaultSettings.watermark_x_space * (defaultSettings.watermark_cols - 1)
		) > page_width
	) {
		defaultSettings.watermark_cols = parseInt(
			(page_width -
				defaultSettings.watermark_x +
				defaultSettings.watermark_x_space) /
			(defaultSettings.watermark_width + defaultSettings.watermark_x_space)
		);
		defaultSettings.watermark_x_space = parseInt(
			(page_width -
				defaultSettings.watermark_x -
				defaultSettings.watermark_width * defaultSettings.watermark_cols) /
			(defaultSettings.watermark_cols - 1)
		);
	}
	//如果将水印行数设置为0，或水印行数设置过大，超过页面最大长度，则重新计算水印行数和水印y轴间隔
	if (
		defaultSettings.watermark_rows == 0 ||
		parseInt(
			defaultSettings.watermark_y +
			defaultSettings.watermark_height * defaultSettings.watermark_rows +
			defaultSettings.watermark_y_space * (defaultSettings.watermark_rows - 1)
		) > page_height
	) {
		defaultSettings.watermark_rows = parseInt(
			(defaultSettings.watermark_y_space +
				page_height -
				defaultSettings.watermark_y) /
			(defaultSettings.watermark_height + defaultSettings.watermark_y_space)
		);
		defaultSettings.watermark_y_space = parseInt(
			(page_height -
				defaultSettings.watermark_y -
				defaultSettings.watermark_height * defaultSettings.watermark_rows) /
			(defaultSettings.watermark_rows - 1)
		);
	}
	var x;
	var y;
	for (var i = 0; i < defaultSettings.watermark_rows; i++) {
		y =
			defaultSettings.watermark_y +
			(defaultSettings.watermark_y_space + defaultSettings.watermark_height) *
			i;
		for (var j = 0; j < defaultSettings.watermark_cols; j++) {
			x =
				defaultSettings.watermark_x +
				(defaultSettings.watermark_width + defaultSettings.watermark_x_space) *
				j;

			var mask_div = document.createElement("div");
			mask_div.id = "mask_div" + i + j;
			mask_div.className = "mask_div";
			var _text = document.createElement("span");
			_text.innerHTML = defaultSettings.watermark_txt;
			mask_div.appendChild(_text);
			//设置水印div倾斜显示
			mask_div.style.webkitTransform =
				"rotate(-" + defaultSettings.watermark_angle + "deg)";
			mask_div.style.MozTransform =
				"rotate(-" + defaultSettings.watermark_angle + "deg)";
			mask_div.style.msTransform =
				"rotate(-" + defaultSettings.watermark_angle + "deg)";
			mask_div.style.OTransform =
				"rotate(-" + defaultSettings.watermark_angle + "deg)";
			mask_div.style.transform =
				"rotate(-" + defaultSettings.watermark_angle + "deg)";
			mask_div.style.visibility = "";
			mask_div.style.position = "fixed";
			mask_div.style.left = x + "px";
			mask_div.style.top = y + "px";
			mask_div.style.overflow = "hidden";
			mask_div.style.zIndex = "9999";
			mask_div.style.pointerEvents = "none"; //pointer-events:none  让水印不遮挡页面的点击事件
			mask_div.style.opacity = defaultSettings.watermark_alpha;
			mask_div.style.fontSize = defaultSettings.watermark_fontsize;
			mask_div.style.fontFamily = defaultSettings.watermark_font;
			mask_div.style.color = defaultSettings.watermark_color;
			mask_div.style.textAlign = "center";
			mask_div.style.width = defaultSettings.watermark_width + "px";
			mask_div.style.height = defaultSettings.watermark_height + "px";
			mask_div.style.display = "block";
			oTemp.appendChild(mask_div);
		}
	}
	document.body.appendChild(oTemp);
}
export default watermark;
